This workshop service repair manual covers the Yanmar 1GM, 2GM, and 3GM series marine diesel inboard engines manufactured between 1980 and 1996. These engines are designed for reliable marine propulsion, operating efficiently in demanding marine environments. The Yanmar 1GM, 2GM, 3GM series engines, available in 1, 2, and 3-cylinder configurations, are known for their robust engineering and dependable performance, making them a trusted choice for various marine applications. This comprehensive manual provides detailed information for maintaining and repairing all models within the Yanmar 1GM, 2GM, 3GM series. It includes step-by-step instructions with illustrations covering a complete A-Z service and repair procedure. Owners, mechanics, and technicians will find essential guidance on recommended service intervals, oil types, oil capacities, and troubleshooting, ensuring the longevity and optimal performance of these diesel engines. The manual is accessible on PC, Mac, tablets, and mobile phones, requiring Adobe Reader.